The proper size for a bra can be determined by taking 2 simple measurements and doing some simple calculations.
NOTE: These sizes are as used in America; there are in addition European and international sizing units. This method does not apply to measuring for a (1) maternity, (2) breast-feeding, or (3) sports bra.
Step 1 - Determining bra size:
(1) Measure the circumference of the chest below the breasts in inches.
(2) Add 5 inches to this measurement.
(3) If this number is even, that is the bra size. If odd, round up to the next even size to get the bra size.
• In Excel the EVEN function performs this rounding up to an even number automatically.
• Manufacturers differ in sizing.
Step 2 - Determining cup size:
(1) Measure the circumference of the chest at the fullest part of the bustline, with the tape horizontal and the arms down.
(2) Subtract this number from the bra size. The cup size is determined based on this difference.
Difference in Inches
0 to 0.5 inch
0.6 to 1.0 inch
1.1 to 2 inches
2.1 to 3 inches
3.1 to 4 inches
4.1 to 5 inches
DD or E
5.1 to 6 inches
6.1 to 7 inches
If the woman has had a single simple mastectomy, then the bra size is unchanged. The cup size is determined by:
(1) Measuring from the center of the chest about the fullest part of the remaining breast to the center of the back.
(2) Multiply this reading by 2 and subtract this from the bra size to determine the cup size, using the table above.
If the woman has had a double mastectomy, then the bra size is unchanged and the cup size depends on the patient's preference.
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